Adult Enteral Nutrition Deciphering the Code Mark H. DeLegge, MD, FACG, AGAF, FASGE Digestive Disease Center Charleston, SC

Indications for EN “If the gut works…use it” EN is the preferred route of nutrition when oral intake is inadequate or a patient is unable to eat.

What Do We Infuse?

Formula Selection Assess digestive and absorptive capacity and GI tolerance Determine kcal, protein, fluid, vitamin and mineral requirements Determine if there are any mineral or electrolyte restrictions Assess indication for specialty formula Identify tube of type and infusion method

What’s the Situation 65 y/o F s/p CVA NG tube for feeding Weight: 60 kg Est kcal needs: 1500kcal/day (25 kcal/kg/day) Est protein needs: 60 gram/d (1 gm/kg) Normal gastrointestinal function No mineral or electrolyte restrictions –Renal disease

Tube Feeding Formulas *Blenderized (Table food) Standard isotonic (Most common) HN - High nitrogen Nutrient dense Fiber-containing Hydrolyzed Specialty

FormulaCal/ccProtein/L (gm) Free H20/L Standard Calorie Dense High Nitrogen Small Peptide Immune Enhancing Hydrolyzed

In Our Patient Normal GI function No need for high protein diet No evidence of renal failure, uncontrolled diabetes No requirement of “high-tech” specialty formula 1500 kcal/24 hours = 60 cc/hr

Blenderized Product Essentially blenderized table food 1 calorie/cc 85.4% water Osmolality: 340 mosmo Lactose-free Moderately expensive  Compleat-B

Standard Enteral Products  Low residue  1 cal/cc  300 mOsmo  Lactose-free  Inexpensive, moderately palatable  Casein protein - biological value lower than other sources of protein

Nutrient Dense Formulas  Low residue  Functional GI tract required  Lactose-free  Inexpensive, moderately palatable  Casein protein  Fluid restricted patients  Renal compromised patients  Nutren 2.0, Magnacal, Jevity 1.5

High Nitrogen Products  Low residue  Functional GI tract required  Lactose-free  Inexpensive, moderately palatable  Casein protein, higher concentration  Patients with wound healing, post-surgical, trauma, sepsis  Example: Replete, Osmolite HN

Peptide-Based Formulas  Protein source: short peptides +/- free AAs  In times of stress small bowel mucosa ability to absorb short peptides increases  Altered GI tract absorption  Critical care  Inflammatory bowel disease  More expensive than standards  Example; Peptamen, Perative

Dipeptides, Tripeptides, Short Peptides Small intestine absorption (PepT1) Fasting: increase in small intestine (PepT1) and (PepT1MRNA) at the small bowel mucosa (peptides in length) Inflammatory gut conditions – increase in small intestine (PepT1) production Ogihara et al; Histochem J, 1999

Elemental Formulas  Macronutrients in most elemental form  Protein: Free AAs  Fat: MCT, long-chain fats  CHO: glucose polymers  Expensive, unpalatable, High osmolality  Example: Crucial, Vital HN, Vivonex

Our Patient 1500 kcal, 60 gm protein, 1800 cc H 2 0 Standard: –1.5 liters (1500 kcal) –66 gm protein –1270 cc/H 2 0 Nutrient dense (2 cal/ cc) –750 cc –63 gm protein –462 cc H 2 0

Specialty Additives

Immune Enhancing Formula

Definition L-Arginine Glutamine Dietary Nucleotides N-3 Fatty Acids Immune Modulating Ingredients

Immune Modulating Nutrition: Meta-Analysis AuthorJournal# of PtsStudiesOutcome HeysAnn Surg Dec infection BealeCCM Dec infection Dec vent HeylandJAMA Dec infection Dec LOS WaitzbergWJS 2006 (in press) Dec infection Dec LOS

Consensus Recommendations Appropriate Patient Populations Patients undergoing elective GI surgery: Greatest benefit in malnourished Trauma patients with ISS  18 or ATI  20 Needs further study Patients with severe sepsis Other patients that may benefit: –Ventilator dependent –Elective surgery (prolonged need for ventilator, cancer with malnutrition) –Severe head injury –Burns  30% (third degree) –Head and neck cancer

Metabolic Effects of Lipids Omega-3 series –Vasodilatory –Anti-inflammatory –Anti-aggregatory –Immunostimulant –Anti-arrhythmic Omega-6 series –Vasoconstrictive –Pro-inflammatory –Pro-aggregatory –Immunosuppressive –Pro-arrhythmic

Enteral Formulations Medium Chain Triglycerides Easier absorption Less pancreatic stimulation Less immune suppressing

Medium Chain Triglycerides 24 HIV + patients with malabsorptive disease LCT vs MCT enriched oral formulas 3 day 100 gm fat diet, then trial diet 3 days Craig et al; JADA, 1997 Gm/Day LCT

Types of Feeding Administration Continuous- given over 24 hours Bolus - syringe feedings given every few hours (e.g. 240cc every 4 hours) Nocturnal - TF given over 8-12 hours at night while patient is sleeping

Conclusion Know the code Assess GI tolerance Determine calorie, water, protein needs Evaluate co-morbidities Determine any special needs Determine infusion method Write the nutrition prescription